<template>  
  <el-container class="home-container">
    <!-- 头部区域 -->
  <el-header>
    <div>
      <img src="../assets/heima.png">
      <span>电商后台管理系统</span>
    </div>
    <el-button type="info" @click="logout">退出</el-button>
  </el-header>
  <!-- 页面主体 -->
  <el-container>
    <!-- 侧边栏 -->
    <el-aside :width="isCollapse ? '64px':'200px'">
      <div class="toggle-button" @click="toggleCollapse">|||</div>
      <!-- 侧边栏菜单区 -->
      <el-menu
      background-color="#333744"
      text-color="#fff"
      active-text-color="#409eff"
      unique-opened
      :collapse="isCollapse"
      :collapse-transition = 'false'
      router
      :default-active='activePath'
      >
      <!-- 一级菜单 -->
      <el-submenu :index="item.id+''"  v-for="item in menulist" :key='item.id'>
        <template slot="title">
          <!-- 图标 -->
          <i :class="iconsObj[item.id]"></i>
          <!-- 文本 -->
          <span>{{item.authName}}</span>
        </template>
        <!-- 二级菜单 -->
        <el-menu-item 
        :index="'/'+subItem.path" 
        v-for="subItem in item.children" 
        :key='subItem.id' 
        @click="saveNavState('/'+subItem.path)">
        <template slot="title">
          <!-- 图标 -->
          <i class="el-icon-menu"></i>
          <!-- 文本 -->
          <span>{{subItem.authName}}</span>
        </template>          
        </el-menu-item>
      </el-submenu>
    </el-menu>
    </el-aside>
    <!-- 内容主体 -->
    <el-main>
      <!-- 路由占位符 -->
      <router-view></router-view>
    </el-main>
  </el-container>
</el-container>
</template>

<script>
export default {
  data(){
    return{
      // 左侧菜单数据
      menulist:[],
      iconsObj:{
        '125':'iconfont icon-user',
        '103':'iconfont icon-tijikongjian',
        '101':'iconfont icon-shangpin',
        '102':'iconfont icon-danju',
        '145':'iconfont icon-baobiao'
      },
      isCollapse:false,
      // 被激活的链接地址
      activePath:''
    }
  },
  created(){
    this.getMenuList()
    this.activePath=window.sessionStorage.getItem('active')
  },
  methods: {
    logout(){
      window.sessionStorage.clear();
      this.$router.push('/login');
    },
    // 获取所有的菜单
    async getMenuList(){
      const {data:res}= await this.$http.get('menus')
      if(res.meta.status !==200)return this.$message.error(res.meta.msg)
      this.menulist=res.data
      console.log(res);
    },
    // 点击按钮切换菜单折叠与展开
    toggleCollapse(){
      this.isCollapse=!this.isCollapse
    },
    // 保存链接的激活状态
    saveNavState(activePath){
      window.sessionStorage.setItem('active',activePath)
      this.activePath=activePath
    }
  },
}
</script>

<style lang='less' scoped>
.home-container{
  height: 100%;
}
.el-header{
  background-color: #373D41;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-left: 0;
  color: #fff;
  font-size: 20px;
  >div{
    display: flex;
    align-items: center;
    span{
      margin-left: 15px;
    }
  }
}
.el-aside{
  background-color: #333744;
  .el-menu{
    border-right: none;
  }
}
.el-main{
  background-color: #eaedf1;
}
.iconfont{
  margin-right: 10px;
}
.toggle-button{
  background-color: #4a5064;
  font-size: 10px;
  line-height: 24px;
  color: #fff;
  text-align: center;
  letter-spacing: 0.2em;
  cursor: pointer;
}
</style>